Today’s Polls, 5/20

In Pennsylvania, Barack Obama leads John McCain by 8 points. SurveyUSA has not polled Pennsylvania since February, but several of Obama’s results have been strong recently in the state. However, one poll will not move his averages all that much, as the state has been polled very densely.

In New Mexico, the two candidates are tied at 44-44. SurveyUSA’s last poll of New Mexico had shown John McCain with a 6 point lead. However, Rasmussen polling conducted last week in New Mexico had shown Obama ahead by 9, so this result can be regarded as a mixed bag.

Two noteworthy features of this polling. Firstly, Senator Clinton was not polled. When we first encountered this issue last week, we developed a workaround for it. Clinton’s result will be listed as “No Poll” in our tables and the numbers will not affect her averages. Note that, because our poll weights are determined in part by whether that pollster had previously polled the matchup in that state, Clinton’s polls now have very slightly different weightings from Obama’s. For example, we weight her 4/12 SurveyUSA result in New Mexico more heavily than we do for Obama, because we do not have any newer data to look at for Clinton. The weights displayed on our poll detail table are the ones applied to Obama.

Secondly, SurveyUSA also included some extremely detailed matchups on prospective Vice Presidential tickets. I have been in contact with the SurveyUSA folks about getting as much detail on these numbers as is possible, and we will be giving these numbers a long look once the rest of their results are in. However, please note that for purposes of our polling averages, only polls without a Vice Presidential candidate are considered, until such time as Obama and McCain actually name their running mates.

Nate Silver is the founder and editor in chief of FiveThirtyEight. @natesilver538